Aspects of the present disclosure relate generally to wireless communication systems, and more particularly, to exploiting the spectrum of a high power base station cell to provide higher capacity in a wireless communication system.
Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power). Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems.
These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. An example of an emerging telecommunication standard is Long Term Evolution (LTE), LTE is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by Third Generation Partnership Project (3GPP). It is designed to better support mobile broadband Internet access by improving spectral efficiency, lower costs, improve services, make use of new spectrum, and better integrate with other open standards using OFDMA on the downlink (DL), SC-FDMA on the uplink (UL), and multiple-input multiple-output (MIMO) antenna technology. However, as the demand for mobile broadband access continues to increase, there exists a need for farther improvements in LTE technology. Preferably, these improvements should be applicable to other multi-access technologies and the telecommunication standards that employ these technologies.
To supplement conventional, relatively high transmit power base stations, e.g., macro base stations or cells, additional restricted power or restricted coverage base stations, referred to as small cells or small coverage base stations or cells, can be deployed to provide more robust wireless coverage to mobile devices. For example, small cells including wireless relay stations and low power base stations (e.g., which can be commonly referred to as Home NodeBs or Home eNBs, collectively referred to as H(e)NBs, femto node, pico nodes, etc.) can be deployed for incremental capacity growth, richer user experience, in-building or other specific geographic coverage, and/or the like. Such low transmit power or small coverage (e.g., relative to the transmit power or coverage of macro network base stations or cells) cells or base stations can be connected to the Internet via broadband connection (e.g., subscriber line (DSL) router, cable or other modem, etc.), which can provide the backhaul link to the mobile operator's network. Thus, for example, the small coverage cells or base stations can be deployed in user homes or in buildings to provide mobile network access to one or more devices via the broadband connection.
Generally, high power base station or cell deployment along with small cell deployment is increasingly seen as a way to guarantee coverage in a given area, to provide services to high mobility users, and to provide other services to users when small cells are overloaded. However, in many locations or at many instances of time, situations that make it favorable for a high power base station cell to provide coverage and services to a user may not occur. As such, in those situations, the spectrum of the high power base station cell may not be optimally utilized, and therefore in these situations, there may be a need to better utilize the spectrum of the high power base station cell.